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111.
以中国和日本两国都市旅游街区的商店招牌为研究对象,以北京琉璃厂、东京浅草寺作为传统旅游街区,以北京王府井、东京新宿作为更新型旅游街区,以南京新街口、东京银座作为都市现代商贸旅游街区,设计了特定的书法景观指数从不同空间尺度探讨了两国书法景观空间分异特征及文化认同的异同。结果表明:全球化背景下中、日两国对书法文化仍然存在的较强文化认同,书法景观作为一种文化符号,标识了城市内部象征空间的形成,表征着全球化背景下的社会与文化过程。虽然两国文字、民俗和书法传统的差异性导致两国在书法艺术的认同角度和形式上的差异,但两国书法景观在整体上具有城市空间分异规律和文化认同的一致性:在全球化的背景下,现代旅游街区的书法景观较之传统旅游街区已经弱化;书法景观在不同类型业态之间的差异则揭示了这种空间分异的形成机制。  相似文献   
112.
黄河三角洲国家级地质遗迹保护区总面积15.3万hm2,与国内外其他河流三角洲沉积相比,黄河三角洲的沉积环境和沉积模式有其独特之处,主要是黄河三角洲平原在发展演化过程中形成的各种河流沉积地貌景观、微地貌景观和河口地貌景观。研究和保护这些地质地貌遗迹,对了解黄河三角洲的演化过程、发展趋势以及提出合理的保护措施有重要意义。  相似文献   
113.
Extreme rainfall events (>50 mm day?1) falling on cultivated land which is relatively bare of vegetation cover, typically give rise to networks of rills and gullies with ephemeral gullies in depressions and valley bottoms. Farming practices such as the removal of field boundaries, the presence of wheelings and rolled surfaces encourage runoff. The coincidence of vulnerable crops such as maize, potatoes and sugar beet with erodible soils and sloping sites may lead to high rates of erosion associated with single events or wet seasons. Not all extreme rainfall events lead to runoff and erosion, this depends on timing with respect to the growing crop. Rates of erosion associated with extreme events may be high but when placed in a long‐term temporal context, they tend to be quite low. Extreme events frequently lead to off‐site impacts most notably muddy flooding of properties and the pollution of watercourses. Landscapes may be protected from extreme events by standard soil conservation techniques; off‐site impacts may similarly be alleviated by flood‐protection measures. In both cases, the challenge is to put in place adequate economic incentives, social pressures and governmental policy frameworks to incentivise effective action. Predicted rainfall changes in the future include wetter winters and increases in rain per rain‐day. In this case, the risk of erosion on cultivated land will increase. However, erosion mitigation strategies should still address the issue of the incidence of high‐risk crops on vulnerable sites. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
114.
朗吉努斯的《论崇高》主要是对五种崇高风格的讨论,在修辞学和美学史上都有重要的意义。从朗吉努斯崇高理论出发,论证了其崇高风格蕴含的辨证思想,即整个文章把握了客观与主观的统一,内容与形式的统一,实践的决定性和正确意识的积极作用,最后由文学理论上升到人类灵魂的崇高境界,完成了一次历史的蜕变。  相似文献   
115.
地理遥感信息模型与地理数学   总被引:10,自引:0,他引:10  
马蔼乃 《测绘科学》2000,25(2):10-14
地理图像信息模型是在地形模型、物理模型、数学模型的基础上提出的一种新型模型。概述了地理图像信息模型的基本概念、技术与应用。提出了符合地理科学自身规律的非线性数学方法 ,解决了确定性问题与不确定问题的结合 ,从形式逻辑计算发展到辩证逻辑的计算 ,从抽象公式的计算发展到抽象思维与形象思维结合的公式与图像合为一体的计算 ,从而解决了地理数学问题 ,为发展地理数学奠定了基础。  相似文献   
116.
Abstract

Landscape stewardship is considered an important place-based approach to addressing sustainability challenges. Working at landscape-level requires collaboration between diverse landscape stakeholders. In this study, we partnered with local stewardship practitioners across six cases in South Africa to investigate how they facilitate collaboration towards social-ecological sustainability outcomes. We found that practitioners facilitate collaboration among stakeholders by operating as relational hubs in the landscape. Through these hubs, they build new inter-personal relationships among stakeholders, creating social networks which enable stewardship practice. The hubs deepen human-nature relationships by creating enabling conditions for stewards to put stewardship ethics into action. Drawing on insights from these cases, we call for a relational approach to landscape stewardship which focuses on human-to-human and human-to-nature relationships. Moreover, we argue that landscape stewardship initiatives need to re-focus stewardship on stewards, recognizing them as key agents of change in addressing the conflict between agriculture and conservation inherent in many landscapes.  相似文献   
117.
118.
地表冻融过程被动微波遥感机理研究进展   总被引:1,自引:0,他引:1  
地表冻融过程及参数特征是陆表过程、气候模式、全球变化等研究的重要方面。被动微波遥感由于具有对土壤水分敏感、高时间分辨率等特点,非常适合用于地表冻融过程的监测和相关参数的反演。在分析地表冻融过程被动微波遥感机理研究发展现状的基础上,面向全球范围内大尺度陆表冻融过程微波遥感算法发展的需求,针对由土壤、积雪和植被组合的复杂地...  相似文献   
119.
Geomorphological development of the eastern margin of the Australian Craton   总被引:1,自引:0,他引:1  
The denudation chronologies of five uplands of contrasting geological structure located at the eastern margin of the Australian Craton are examined. They are the Isa Highlands, MacDonnell Ranges and Flinders Ranges (fold mountains, orogenic setting); the Arcoona Plateau (dissected plateau, platform setting); and the Gawler Ranges (massif of old silicic volcanics, cratonic setting). In each, surfaces of Mesozoic age, many of them exhumed and of pre-Cretaceous age, are preserved. Each also appears to have been uplifted recurrently. Each was either overwhelmed or bordered by the Early Cretaceous (Neocomian-Aptian) sea. Tectonism associated with the break-up of Gondwana probably allowed this important marine transgression. Thereafter, thalassostatic and erosional/depositional isostatic responses have maintained the uplands as uplands and the intervening basins as negative topographic and structural units; the pattern of topography has been constant for the last 60–100 Ma.  相似文献   
120.
Studies of coffee agroecosystems have focused on their role in providing habitat for biodiversity across a range of management intensities. These studies have not taken into account the temporal and spatial transformations in coffee landscapes and their impacts on structural heterogeneity and biodiversity, nor systematically linked these transformations to farmer management responses to price and policy shocks. We utilize a coupled natural–human system framework to examine the historical transformations of the coffee landscape in a matrix of community-protected forests in a coffee-growing community in Oaxaca, Mexico, and study how those transformations impact tree biodiversity across a range of management options, including formerly certified organic and conventional coffee, abandonment, and conversion. The coffee landscape has historically transitioned from forests and fields (1950s–1960s) to one dominated by coffee (1970s–1980s) to a richly mosaic and biodiverse landscape (1990–2010) resulting from 43% recent abandonment and conversion of coffee back to forest and fields.  相似文献   
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